NEW YORK — The three 18-year-olds, friends since middle school, are about to go off separately to college this fall. But on Sunday, these avid fans of the Batman film franchise had no doubt where they wanted to be: together, at the movies, watching “The Dark Knight Rises.”

“What happened in Colorado was horrible, but that guy was just a psycho,” said Sahil Agrawal, of Queens in New York City, waiting with friends David Kim and Danny Wong for an Imax showing on Manhattan’s Upper West Side. “This wasn’t going to change our plans.”

The three were typical of hordes of fans who packed theaters across the country over the weekend, keeping plans to see the final installment of the phenomenally successful Batman trilogy despite Friday’s horrific shooting in Colorado. Despite the occasional jitter — reflected in the choice of a back-row seat, perhaps, or a glance to see what security was in place — moviegoers seemed determined to look beyond the shooting.

“I’m not going to let some nut who shoots people dictate what I’m going to do,” said Ron Bondy, 36, in Bismarck, N.D., a sentiment echoed by fans all over the country.

Not that there weren’t some evident qualms. At the same theater in Bismarck, Jen Jackson had insisted upon one thing to her husband: They were going to sit in the back row in case they needed to get out fast. The 29-year-old architect was also forgoing the popcorn — not as a precaution, but because nerves had stolen her appetite.

“I’ll be honest, I’m kind of scared,” said Jackson. She had hesitated to come at all. But her husband, Patrick, standing alongside her, was pragmatic: “I don’t think anything would happen in Bismarck.”

And Sunday evening at a Pittsburgh-area theater, some moviegoers — whom a police official called “jumpy” in the wake of the shooting — rushed to the exits when a fight broke out outside. The showing was halted, and customers were given passes to attend another time. No one was arrested.

On Monday afternoon, Warner Bros. released its weekend revenue reports — it and other studios had withheld usual Sunday estimates out of respect for the victims. The film brought in $160.9 million — millions lower than some had predicted before the shooting, but still making it the third highest opening weekend ever, after “The Avengers” and “Harry Potter and the Deathly Hallows — Part 2.”

Katie Birkel, for one, had no intention of missing the occasion. She was at a Manhattan showing Sunday along with three friends, celebrating one of their birthdays. Birkel said she had been inspired by a statement from the film’s director, Christopher Nolan, after the tragedy, which occurred at the midnight showing in Aurora, Colo.

“He said that movies are about coming together and sharing an experience,” noted Birkel, 28. “I agree with that.”

Mike Sumner, standing a few steps behind her in a Batman T-shirt, said he was comforted by seeing the NYPD outside the theater — at least two officers were patrolling outside. “Colorado was an isolated incident,” he said. “I’m not afraid of copycats. Besides, I’m a New Yorker. We’re always vigilant.”

Police were also visible outside a theater in McAllen, Texas, near the Mexico border, where an officer firmly waved away drivers who attempted to stop in front.

Inside, Juan Carlos Rivera waited with his mother-in-law and his wife. The 38-year-old Brownsville resident said the family had been big fans of the first two movies and wouldn’t want to skip the third.

“It looks like it was an isolated incident,” Rivera said of the mass shooting. He said he’d probably sit on the aisle — not out of fear, but because his wife was pregnant and might need the restroom. “You can’t allow a random event like that to terrorize you,” he said.

Besides, many said in interviews, what was the chance that lightning would strike twice?

“I don’t think that that many people are crazy enough,” reasoned Dayna Freeman of Kansas City, Mo.

Her date, Tom Meyer, added that the theater — the Cinemark Palace at The Plaza — had excellent security. The two had bought their tickets on Sunday, but like most interviewed, they said the shooting in no way had sparked their curiosity. “No, I can’t imagine anything like that,” said Meyer.

Meyer added that he didn’t think the content of the movie had anything to do with the crime: “You can’t really attribute the actions of a nut to the movies,” he said. “Two years ago, he would have picked ‘Avatar.'”

Still, despite sharing that logic, some were showing nerves. In Hollywood, Fla., Steve Parenteau, 45, said he wasn’t thinking at all about the shooting. But his 13-year-old son, Noah, looked solemn, saying the Colorado tragedy was on his mind. “It’s scary,” he said. “I can picture it.”

And at a multiplex in downtown Chicago, roommates Sarah Cantor and Brittany Carter avoided a midnight showing. “I was relieved to know that we were going to a matinee,” said Cantor, 23.

Still, most moviegoers echoed the feeling that the attack could have happened anywhere, anytime.

“Things are going to happen wherever they’re going to happen, because people are nuts wherever,” said Rachel Cox, who saw the movie at Atlanta’s Midtown Arts Cinema. “Crazy travels, so I don’t really think it has anything to do with geography or the movie … crazy people are crazy.” Still, she added, she planned to sit in the back — because she likes the view from there, but also because she considered it safer, even before Colorado.

In midtown Manhattan, Randy Cordero and Megan Rivera sat on the pavement outside an AMC Loews Theater, waiting with soft drinks and a magazine for a late-afternoon show. They’d bought their tickets online Saturday, and said the shooting hadn’t affected their plans. They’d hoped for a midnight showing, but it was sold out.

“I don’t think it’ll happen to me, but it can always happen,” noted Cordero. But Rivera said there was one thing that would indeed cause her some concern: seeing someone in costume, especially as the Joker (New York’s police commissioner, Ray Kelly, said the shooter, James Holmes, had his hair painted red and said he was the Joker, but Aurora police have not confirmed that.) “I’d feel more cautious, and I’d think, ‘I’ve got to watch that guy,'” she said.

Waiting for an earlier show at the same theater was Devin Favors, 24, an event ticket broker from Brooklyn. He said he’d bought his ticket last week, but even if he hadn’t, nothing would have stopped him from seeing the movie.

After all, he said, “This is America. And you should be able to go where you want to go, and see what you want to see.”